* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --primary-light: #93c5fd;
    --dark: #1e293b;
    --gray: #64748b;
    --light-gray: #f1f5f9;
    --white: #ffffff;
    --success: #10b981;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

body {
    font-family: 'Inter', sans-serif;
    background: var(--light-gray);
    color: var(--dark);
    line-height: 1.5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Navigation */
nav {
    background: var(--white);
    border-bottom: 1px solid #e2e8f0;
    position: sticky;
    top: 0;
    z-index: 100;
}

nav .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 700;
}

.logo i {
    color: var(--primary);
    font-size: 1.6rem;
}

.logo span {
    color: var(--dark);
}

.logo span span {
    color: var(--primary);
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--gray);
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--primary);
}

/* Hero */
.hero {
    text-align: center;
    padding: 3rem 0 2rem;
    background: linear-gradient(135deg, #eff6ff 0%, #ffffff 100%);
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(59, 130, 246, 0.1);
    padding: 0.35rem 1rem;
    border-radius: 100px;
    color: var(--primary);
    font-size: 0.8rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.gradient {
    color: var(--primary);
}

.hero-subtitle {
    font-size: 1.1rem;
    color: var(--gray);
    max-width: 550px;
    margin: 0 auto 1.5rem;
}

.trust-badges {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.trust-badges span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.85rem;
    color: var(--gray);
}

.trust-badges i {
    color: var(--success);
}

/* Converter Card */
.converter-card {
    background: var(--white);
    border-radius: 1.5rem;
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    margin: 2rem 0;
}

/* Upload Area */
.upload-area {
    margin: 2rem;
    padding: 3rem;
    border: 2px dashed #cbd5e1;
    border-radius: 1rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
    background: #fafbff;
}

.upload-area:hover {
    border-color: var(--primary);
    background: #f0f4ff;
}

.upload-area.drag-over {
    border-color: var(--primary);
    background: #eff6ff;
}

.upload-content i {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: 1rem;
}

.upload-content h3 {
    margin-bottom: 0.5rem;
}

.upload-content p {
    color: var(--gray);
    font-size: 0.85rem;
}

/* Settings */
.settings-panel {
    padding: 0 2rem;
    border-top: 1px solid #e2e8f0;
    border-bottom: 1px solid #e2e8f0;
}

.settings-grid {
    padding: 1.5rem 0;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.setting-group label {
    font-weight: 600;
    margin-bottom: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.setting-group label i {
    color: var(--primary);
}

/* Format Selector */
.format-selector {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.format-btn {
    padding: 0.6rem 1.2rem;
    border: 1px solid #e2e8f0;
    background: var(--white);
    border-radius: 0.5rem;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.2s;
}

.format-btn:hover {
    border-color: var(--primary);
    background: #eff6ff;
}

.format-btn.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

/* Checkbox */
.checkbox-row {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
}

.checkbox-label input {
    width: 18px;
    height: 18px;
    cursor: pointer;
    accent-color: var(--primary);
}

/* Convert Button */
.convert-btn {
    margin: 2rem;
    padding: 1rem;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 0.75rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    width: calc(100% - 4rem);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.convert-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

.convert-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* Progress */
.progress-area {
    margin: 0 2rem 2rem;
    padding: 1rem;
    background: var(--light-gray);
    border-radius: 0.75rem;
}

.progress-bar {
    height: 6px;
    background: #e2e8f0;
    border-radius: 3px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--primary);
    width: 0%;
    transition: width 0.3s;
}

.progress-message {
    margin-top: 0.5rem;
    font-size: 0.8rem;
    color: var(--gray);
}

/* Results */
.results-area {
    padding: 0 2rem 2rem;
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid #e2e8f0;
}

.results-header h3 {
    font-size: 1rem;
}

.zip-btn {
    padding: 0.4rem 1rem;
    background: var(--success);
    color: white;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 0.85rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.images-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 1rem;
}

.image-card {
    background: var(--white);
    border-radius: 0.75rem;
    overflow: hidden;
    border: 1px solid #e2e8f0;
    transition: all 0.2s;
}

.image-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.image-card img {
    width: 100%;
    height: 140px;
    object-fit: contain;
    background: #f8fafc;
}

.image-info {
    padding: 0.6rem;
    text-align: center;
}

.image-name {
    font-size: 0.7rem;
    color: var(--gray);
    margin-bottom: 0.5rem;
    word-break: break-all;
}

.download-single {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    background: var(--primary);
    color: white;
    padding: 0.3rem 0.7rem;
    border-radius: 0.4rem;
    text-decoration: none;
    font-size: 0.7rem;
}

.download-single:hover {
    background: var(--primary-dark);
}

/* Features */
.features-section {
    padding: 4rem 0;
    background: var(--white);
}

.section-title {
    text-align: center;
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 2.5rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.feature-card {
    text-align: center;
    padding: 1.5rem;
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: #eff6ff;
    border-radius: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
}

.feature-icon i {
    font-size: 1.5rem;
    color: var(--primary);
}

.feature-card h3 {
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.feature-card p {
    color: var(--gray);
    font-size: 0.85rem;
}

/* How To */
.howto-section {
    padding: 4rem 0;
    background: var(--light-gray);
}

.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 2rem;
    text-align: center;
}

.step-number {
    width: 45px;
    height: 45px;
    background: var(--primary);
    color: white;
    font-size: 1.3rem;
    font-weight: 700;
    border-radius: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
}

.step h3 {
    margin-bottom: 0.5rem;
    font-size: 1rem;
}

.step p {
    color: var(--gray);
    font-size: 0.8rem;
}

/* Footer */
footer {
    background: var(--dark);
    color: #94a3b8;
    padding: 2rem 0 1rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid #334155;
}

.footer-logo {
    font-size: 1.2rem;
    font-weight: 600;
}

.footer-logo i {
    color: var(--primary);
}

.footer-logo span {
    color: var(--primary);
}

.credit-link {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
    margin-left: 0.25rem;
}

.credit-link:hover {
    text-decoration: underline;
}

.footer-meta {
    font-size: 0.8rem;
}

.footer-bottom {
    text-align: center;
    padding-top: 1.5rem;
    font-size: 0.7rem;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    padding: 0.75rem 1.25rem;
    border-radius: 0.5rem;
    color: white;
    font-size: 0.85rem;
    transform: translateX(400px);
    transition: transform 0.3s;
    z-index: 1000;
}

.toast.show {
    transform: translateX(0);
}

.toast.success { background: var(--success); }
.toast.error { background: #ef4444; }
.toast.info { background: var(--primary); }

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .upload-area {
        margin: 1rem;
        padding: 2rem;
    }
    
    .convert-btn {
        margin: 1rem;
        width: calc(100% - 2rem);
    }
    
    .settings-panel {
        padding: 0 1rem;
    }
    
    .results-area {
        padding: 0 1rem 1rem;
    }
    
    .nav-links {
        gap: 1rem;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
}